Meta-anilide urea compositions and their utility as herbicides

ABSTRACT

META-ANILIDE UREA COMPOSITIONS HAVE THE FORMULA:   1-(R2-N(-R3)-C(=X)-N(-R1)-),3-(R5-C(=Y)-N(-R4)-),(Z)M-   BENZENE   IN WHICH X AND Y ARE, INDEPENDENTLY, OXYGEN AND SULFUR; R1 IS HYDROGEN OR LOWER ALKYL; R2 AND R3 ARE, INDEPENDENTLY, HYDROGEN, ALKYL, LOWER ALKOXY, HALOALKYL, LOWER ALKENYL, CYCLOALKYL HAVING FROM 3 TO 6 CARBON ATOMS, INCLUSIVE, CARBALKOXYALKYL, FURFURYL, NAPTHYL, PHENYL OR SUBSTITUTED-PHENYL, INCLUSIVE, IN WHICH THE SUBSTITUENTS ARE HALOGEN, NITRO, OR LOWER ALKOXY; R4 IS HYDROGEN OR LOWER ALKYL; R2 IS HYDROGEN, ALKYL, ETHYL CYCLOALKYL, LOWER ALKENYL, HALOGENATED LOWER ALKYL, CYCLOALKYL HAVING 3 TO 6 CARBON ATOMS, INCLUSIVE, PINONYL 2,4-DICHLOROPHENOXYMETHYLENE, BENZYL, PHENYL, OR SUBSTITUTED-PHENYL IN WHICH THE SUBSTITUENTS ARE HALOGEN, NITRO, LOWER ALKYL, LOWER ALKOXY OR TRIHALOMETHYL; Z IS HALOGEN, LOWER ALKYL, NITRO AMINO OR TRIFLUOROMETHYL, AND M IS AN INTEGER HAVING A VALUE FROM 0 TO 4, INCLUSIVE, PROVIDED THAT WHEN R1, R2, R3 AND R4 ARE EACH HYDROGEN, X AND Y ARE EACH OXYGEN AND M IS 0, THEN R5 IS OTHER THAN METHYL OR ETHYL. THE COMPOUNDS ARE USEFUL AS HERBICIDES AND THEY EXHIBIT BOTH PRE-EMERGENCE AND POST-EMERGENCE ACTIVITY. REPRESENTATIVE COMPOUNDS ARE: 1-(3&#39;&#39;-ISOBUTYRAMIDOPHENYL)-3-METHYL UREA, 1-CYCLOHEXYL-3-(3&#39;&#39;-PROPIONAMIDOPHENYL)UREA, 1-BUTYL-3-(3&#39;&#39;-PROPIONAMIDOPHENYL)UREA, 1-BUTYL-3-(3&#39;&#39;-ISOBUTYRAMIDOPHENYL)UREA, 1-(3&#39;&#39;-NITROPHENYL)-3-(3&#39;&#39;-ISOBUTYRAMIDOPHENYL)UREA, 1-N,N-DIMETHYL-3-(PIVALAMIDOPHENYL)UREA, 1-(3&#39;&#39;-PROPIONAMIDOPHENYL)-3-N-BUTYL THIOUREA, AND 1-(3&#39;&#39;-PESTAFLUOROPROPIONAMIDOPHENYL)-3,3-DIMETHYL UREA.

States Patent Us. Cl. 260-553 A 25 Claims in which X and Y are,independently, oxygen and sulfur; R118 hydrogen or lower alkyl; R; and Rare, independently, hydrogen, alkyl, lower alkoxy, haloalkyl, loweralkenyl, cycloalkyl having from 3 to 6 carbon atoms, inclusive,carbalkoxyalkyl, furfuryl, naphthyl, phenyl or substituted-phenyl,inclusive, in which the substituents are halogen, nitro, or loweralkoxy; R is hydrogen or lower alkyl, R is hydrogen, alkyl, ethylcycloalkyl, lower alkenyl, halogenated lower alkyl, cycloalkyl having 3to 6 carbon atoms, inclusive, pinonoyl2,4-dichlorophenoxymethyleneybenzyl, phenyl, or substituted-phenyl inwhich the substituents are halogen, nitro, lower alkyl, lower alkoxy ortrihalomethyl; Z is halogen, lower alkyl, nitro, amino orttifluoromethyl, and m is an integer having a value from 0 to 4,inclusive, provided that when R R R and R are each hydrogen, X and Y areeach oxygen and m is 0, then R is other than methyl or ethyl. Thecompounds are useful as herbicides and they exhibit both pre-emergenceand post-emergence activity. Representative compounds are:

This application is a continuation-in-part of copending application Ser.No. 746,007, filed July '19, 1968, now abandoned, which in turn is acontinuation-in-part application of Ser. No. 662,573, filed Aug. 23,1967, now abandoned.

This invention relates to certain novel meta-anilide ureas which areuseful as herbicides. More specifically,

this invention relates to certain substituted organo-anilide ureas andto the preparation and utility of the compounds as herbicides.

3,642,891 Patented Feb. 15, 1972 4 r The compounds of the presentinvention correspond to the formula: 1

in which X and Y are independently selected from the group consisting ofoxygen and sulfur, R is hydrogen or lower alkyl, R; and R areindependently selected from the group consisting of hydrogen, alkyl,lower alkoxy, haloalkyl, lower alkenyl, cycloalky-l having from 3 to 6carbon atoms, inclusive, carbalkoxyalkyl, furfuryl, naphthyl, phenyl,substituted-phenyl in which said substituents are selected from thegroup consisting of halogen, nitro, and lower alkoxy; R is hydrogen orlower alkyl; R is selected from the group hydrogen, alkyl,ethylcycloalkyl, lower alkenyl, halogenated lower alkyl, cycloalkylhaving from 3 to 6 carbon atoms, inclusive, pinonoyl,2,4-dichlorophenoxymethylene, benzyl, phenyl, substituted-phenyl inwhich said substituents are selected from the group consisting ofhalogen, nitro, lower alkyl, lower alkoxy and trihalomethyl; and Z isselected from the group consisting of halogen, lower alkyl, nitro, aminoand trifluoromethyl, and m is an integer having a value from 0 to 4,inclusive, preferably 0 to 2., inclusive, provided that when R R R and Rare each hydrogen, X and Y are both oxygen and m is 0, then R is otherthan methyl or ethyl.

One embodiment of the invention includes compounds having the formula:

II NHCNHRa in which R, and R are each alkyl having 1 to 10 carbon atoms.

As employed in this specification, the terms lower alkyl and loweralkoxy preferably include those members of the group containing from 1to 6 carbon atoms, inclusive, in either a straight chain or a branchedchain configuration. Similarly, the termalkyl preferably includes thosemembers of the group containing 1 to 10 carbon atoms, inclusive. Theterm lower alkenyl preferably includes those members of the groupcontaining at least one olefinic bond and containing from 2 to 4 carbonatoms, inclusive. The term carbalkoxyalkyl preferably includes thosemembers of the group containing from 3 to 6 carbon atoms, inclusive. Theterm halogen, as employed herein and in the terms haloalkyl, halogen,halogenated, trihalomethyl, preferably includes fluorine, chlorine andbromine.

The compounds of the present invention are prepared by several methods.Two such methods applicable m preparing the compounds is thecondensation between the appropriate meta-amino substituted anihde witheither an isocyanate or carbamoyl chloride and also the condensation ofthe appropriate meta-amino urea and e1ther an acyl halide or acidanhydride. These methods will be further exemplified below. Similarly,an isothiocyanate is employed to prepare the thiourea derivatives. Whenthe unsubstituted amidophenyl urea is prepared a cyanate salt is reactedwith the appropriate substituted amido aniline; .The reactions proceedreadily in the liquid phase. The

employment of a solventis also useful, facilitating processing, as wellas agitation of the reactants. Solvents such as water, benzene, toluene,acetone, tetrahydro'furan, and the like, are employed. A catalyst may beemployed to enhance the reaction although a catalyst is not required.Catalysts such as e.g. dibutyltin dilaurate and anhydrous potassiumcarbonate and copper powder, are effective catalysts. The reactions arecarried out at temperatures that permit operation in the liquid phase.These temperatures are between about room temperature and refluxtemperature of the solvent if a solvent is employed. Prefera-bly, thereaction mixture is refluxed at an elevated temperature.

Compounds of the present invention are prepared in accordance with thefollowing illustrative examples.

EXAMPLE 1 Preparation of 1-(3-isobutyramidophenyl)-3-methyl ureaMeta-amino isobutyranilide, 12.5 g. (0.07 mole), is disvolved in 100 ml.of acetone containing a few drops of dibutyltin dilaurate. Methylisocyanate, 4.4 g. (0.077 mole), is added to the mixture. The mixture isrefluxed for two hours. On cooling, the crystalline product is filteredoff and dried. There is obtained 8.2 g. (50 percent of theory) of thetitle compound, M.P. 168-171 C.

EXAMPLE 2 Preparation of l-(3'-pivalamidophenyl)-3,3-dimethyl ureaMeta-amino pivalanilide 15.4 g. (0.08 mole) is dissolved in 100 ml. ofacetone containing 11 g. of finely powdered anhydrous potassiumcarbonate and a trace of copper powder. Dimethylcarbamoyl chloride 8.6g. (0.08 mole) is added and the mixture is refluxed for 8 hours withstirring. The solid is filtered off and the acetone is removed undervacuum. The viscous liquid product is triturated with ether andcrystallizes. It is Washed with water, and hydrochloric acid solutionand is dried. There is obtained 12.5 g. (60 percent of theory) of thtitle compound, M.P. 181-l86 C.

EXAMPLE 3 Preparation of 1-(3'-propionarnidophenyl)-3-nbutyl thioureaMeta-propionamidoaniline, 8.2 g. (0.05 mole), is dissolved in 50 ml. ofacetone. To this solution is added 5.8 g. of n-butylisothiocyanate. Theresulting mixture is refluxed for two hours. After cooling, ibis-poured.onto crushed ice and washed with Water. After filtering, the product isdried in vacuum. There is obtained 13.8 g. (98.5 percent of theory) ofthe title compound, M.P. 136-138 C.

EXAMPLE 4 Preparation of 3'-propionamidophenyl 'ureaMeta-propionamidoaniline, 8.2 g. (9.05 moles) is dis solved in 100 ml.of dilute hydrochloric acid solution. Potassium cyanate, 4.1 g. isdissolved in IIIL Of'WaICI' and this is added to the above acidsolution. The resulting mixture is maintained at -40 C. for three hours.After cooling, the crystals are filtered and washed with Water. They aredried further in vacuum. There is obtained 8.9 g. (86 percent of theory)of the ,title compound, M.P. l88l90 C.

EXAMPLE 5 Preparation of 1-(3'-butyramidophenyl)-3-methyl urea.N-meta-arninophenyl-N-methyl urea, 11.5 g. (0.07 mole) is suspended inml. of ether and 11.1 g. of nbutyric anhydride containing 5 drops ofconcentrated sulfuric acid is added dropwise. The mixture is heated atreflux for 1 hour. The mixture is cooled and the product filtered off.The product is washed successively with dilute (5%) sodium hydroxide,dilute (5%) HCl, and water and then dried. There is obtained 11.2 g. (68percent of theory) of the title compound, M.P. 158159 C.

EXAMPLE 6 Preparation of 1-(3'-cyclohexanecarboxamidophenyl) -3-methylurea N-rneta-aminophenyl N methyl urea 11.5 g. (0.07 mole) dissolved inacetone containing 7 .7' g. (0.076 mole) of triethylamine and 11.3 g. ofcyclohexane carbonyl chloride is added dropwise with stirring. Theproduct precipitates from the acetone and is filtered off washed withwater and then dried. There is obtained 16.0

1 g. (83 percent of theory) of the title compound, M.P.

X B g NR; N

NR4CR TABLE I Compound Number X R; z

oooooooooooooooooooooo oooooooooooooooooooooooo 4wmmmmmmmmmmmmmmmmmmmmmm mmmmmmmmmmmmmmmmmmmmegm w Cyelohexyl.

TABLE I-Continued Compound 7 Number CH C (CH3)3 166-169 T-T 106-112 CH3138-141 n-CaH1 139-142 OH=C (CH3) 3 68-73 CH CHKJHM- 113-116 8g2C CH3 3173-78 mm:mmmmmmmmmmmmmmmmmmgmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmu:mmmmmn:mmmmmmgmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm Ed oooooooooooooooooooooo ooooobcooooooooooooooocoooooooooo'oooooooodoooooooooooooooooo0ooooobooooooooooooooooooooooooooooooooo'oooooooooooooooooommmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm1113 melting point. C

OQO OOOOOOOOQOOOOQOOOOOOOQOOOOOOO 4 06010000OOOOOOOOOOOOOO OO OOOOObOOmun-1mmmmmmmmmmmmmmcdmmmmmmmmmmmmmm 5 mmmmmgmmmmmmmmmmmmgmmmmmmmmmmC(CH3 2CH2C1 CHzCH (CH3) C211 138-140 01120 (CH3) 2021215. 163-166 GEXCHQ C4Hn 162-164 CH2OH(CH3)CH2C (CH3) 132-135 3 CClzCHg -159 CH; CH (CH3)115. 136-138 CH C (CH3)2C2H5.. 137-140 CH(C2H5)C4HU -162 CH(CgH5) C41191 -167 CClzOF 151-154 TABLE I-Continued Compound mp melting Number X Y RR R3 Z point. C:

O O H CH CClzCFQ 105-110 O H H F- 194-196 0 O H H 150-160 0 O H H195-107 0 O H H 219-221 0 O H H ZCI-Phenyl... 155-150 0 O H H3-C1-phenyl. 301-305 0 O H H 4-Cl-phe11yL. 314-317 0 O H H2,4-dlCl-phcnyl 216-219 0 O H H 3, 4-d1 cl-phenyl 03-205 0 0 H CH3 2-CH3-phonyL 129-132 0 O H CH 3-CH3-pl1euyl 144-147 0 O H CH3 4-CH -pheny1173-175 0 O H CH 2-Cl-phenyl. 101-105 0 O H CH3 3-Cl-pl1enyl. 175-178 0O H CH3 4-Cl-pl1enyl 1.195 O O H CH 2,4-di-Cl-phenyl 102-107 0 O H CH;3,4-di-Cl-phenyl 96-99 0 O H CH3 F 90-105 0 O H CH3 Glass 0 O H CH3105-108 0 O H CH Glass 0 0 H CH3 Glass 0 O H CH3 Glass 0 0 H CH3 Glass 0O H CH Glass 0 O H CH3 Glass 0 O H CH3 Glass 0 O H CH3 65-68 0 O H CH362-64 0 O H CH3 1. 5460 O O H OCH3 148-150 0 0 H OCHa 140 O O H 0 CH3118-110 0 O H OCH3 107-110 0 O H OCH3 1. 5468 O 0 H 0 CH3 1. 5463 O O HOCH3 1. 5410 O 0 H 0 CH3 1. 5802 O O H 0 CH3 1. 5943 O O H OCH3 1. 5823O O H 0 CH3 139-143 0 O H CH3 1. 5908 O O H CH3 114-116 0 O H CH3 Glass0 O H CH3 1. 5467 O O H CH3 1. 5613 O O H CH 1. 5548 O O H CH3 129-131 0O H CH 1. 5570 1 When heated rapidly. 2 Sodium salt.

Other examples of compounds falling within the generic (Rumex crispus(L.)). Ample seeds are planted to 'give formulas presented herein, whichare preparable by the aforedescribed procedures and which may beformulated into herbicidal compositions and applied as herein illusabout20 to seedlings per row, after "emergence, depending on the size of theplants. The flats arewatered after planting. The spraying solution isprepared by distrated are: solving 50 mg. of the test compound in 3 ml.of a solvent,

X Y R1 R R3 R4 R5 Z S C1H5 CH3 0 CgHs CH3 0 H O H CH3 S H CH3 S H 0 115O n-C Hq H O H H yl O H H 3-Ol-pheny1 5'-NO O O H H 3,4-diCl-phenyl 5-N0O H CH 4-NO;-phenyl. 5-NH3 O H H 4-OCH3-Dheny1 5-CH O H C H3 H H 4-CC1-phenyl 5-Br; O H 3-Cl-phenyl H H 4-CF3-phenyL. 5-CF O H H n-C3H1 H CCl35'-NH O H H C(CHshBr S CH H CH CH Cl. 5-NO; O H H CF 5CH O H H Benzylmanner.

Pre-emergence herbicide test.0n the day preceding treatment, seeds ofseven dilferent weed species are planted in individual rows using onespecies per row across the width of the flat. The seeds used are hairycrabgrass Herbicidal screening tests such as acetone, containing 1%Tween 20 (polyoxy- (Digitaria sanguinalis (L.) Scop.), yellow foxtail(Setaria glauca (L.) Beauv.), watergrass (Echinochloa crusgalli ('L.)Beauv.), California red oat (Avemz sativa (L.)), redroot pigweed(Amaranthus retroflexus -(L.), Indian +=slight injur (25-35 percentcontrol) ++=moderate injury (-65 percent control) ethylene sorbitanmonolaurate). The following day each flat is sprayed at the rate of 20pounds of the candidate compound per 80 gallons of solution per acre. Anatomizer is used to spray the solution on soil surface. The flats areplaced in a greenhouse at 80 F. and watered regularly. Two weeks later,the degree of weed control is determined by comparing the amount ofgermination and growth of each weed in the treated flats with weeds inseveral untreated control flats. The rating system is as follows:

I -=no significant injury (0-15 percent control) mustard (Brassicajuncea (L) Coss.) and curly dock +++=severe injury or death (-100percent control) T 768 2 8 .1 3 1888 8 8 7 888 7 on 0 on 88868888007 800 20 8 00 8 lmmmmmmmlllmunmmmw1 1B11mmm1H mmwmmMmm1111111unvmmum1m1m111 1 1 1m1m111 111111m. .m1mmmumunmmm lmmmmmml. .1m...

1 SCREENihIGr Post- I. i emergence TABLE II.HERBICIDAL. ACTIVITRESULTS-Continued Pre- I emergence is the sum of the'numbef Compound Number An 'acitivity index is l'ised to represent the total activity onall seven -Weed species. It of plus ma'rks, so that an activity index of21 represents complete control ofall seven weeds. The resultsof thisTABLE rr-nnamcibnr. ACTIVITY} SCREENING fillL ic a i ued H Post-21=85100% control of all seven plant species tested preemergence.18=85100% control of all six plant; species tested post-emergence.

The new compounds of the present invention are used as pre-emergence orpost-emergence herbicides and are applied in a variety of ways atvarious concentrations. In practice, the compounds are formulated withan inert carrier, utilizing methods well-known to those skilled in theart, thereby making them suitable for application as dusts, sprays, ordrenches and the like in the form and manner required. The mixtures canbe dispersed in water with the aid of a wetting agent or they can beemployed in organic liquid compositions, oil and water, water in oilemulsions, with or without the addition of wetting, dispersing oremulsfying agents. The amount applied depends upon the nature of theseeds or plants to be controlled and the rate of application varies fromapproximately 1 to approximately 50 pounds per acre. One particularlyadvantageous Way of applying the compound is a narrow band along a rowcrop straddling the row. In practice, the compounds are formulated withan inert carrier utilizing methods well known to those skilled in theart, thereby making them suitable for particular application.

The phytotoxic compositions of this invention are applied to the plantsin the conventional manner. Thus, the solid and liquid compositions canbe applied to the plant by the use of, for example, power-dusters, boomand hand sprayers and spraydusters. The compositions can also be appliedfrom airplanes as a dust or a spray because they are effective in verylow dosages. In order to modify or control growth of germinating seedsor emerging seedlings, as a typical example, the dust and liquidcompositions are applied to the soil according to conventional methodsand are preferably distributed in the soil to a depth of at least/2-inch below the soil surface. It is not necessary that the phytotoxiccompositions be admixed with the soil particles and these compositionscan be applied merely by spraying or sprinkling the surface of the soil.The phytotoxic compositions of this invention can also be applied byaddition to irrigation water supplied to the field to be treated. Thismethod of application permits the penetration of the compositions intothe soil as the water is absorbed therein. Dust compositions, granularcompositions or liquid formulations applied to the surface if the soilcan be distributed below the surface of the soil by conventional meanssuch as discing, dragging or mixing operations.

The phytotoxic compositions of this invention can also contain otheradditaments, for example, fertilizers, pesticides and the like, used asadjuvant or in combination with any of the abovedescribed adjuvants.Other phytotoxic compounds useful in combination with theabove-described compounds include for example, 2,4-dichlorophenoxyaceticacids, 2,4,S-trichlorophenoxyacetic acid, 2'-methyl-4-chlorophenoxyacetic acid and the salts, esters and amidesthereof; triazine derivatives, such as 2,4-bis (3-methoxypropylamino)-6-methylthio S triazine; 2-chloro 4 ethylamino 6isopropylamino S triazine, and 2-ethylamino 4isopropylamino-6-methylcercapto-S-triazine, urea derivatives, such as3-(3,4-dichlorophenyl)-l,l dimethyl urea and3-(p-chlorophenyl)-l,l-dimethyl urea and acetamides such asN,N-diallyl-a-chloroacetamide, N- (a-chloroacetyl) hexamethylene imine,and N,N-diethyla-bromoacetamide, and the like; benzoic acids such as 3-amino-2,5-dichlorobenzoic and; thiocarbamates, such as S- propyldipropylthiocarbamate; S-ethyl-dipropylthiocarbamate, S-ethyl-cyclohexylethyl thiocarbamate, S-ethyl hexahydro-lH-azepine-l-carbothioate and thelike. Fertilizers useful in combination with the active ingredientsinclude for example, ammonium nitrate, urea and superphosphates. Otheruseful additarnents include materials in which plant organisms take rootand grow such as compost, manure, humus, sand and the like.

The concentration of a compound of the present invention, constitutingan effective amount in the best mode of administration in the utilitydisclosed is readily determinable by those skilled in the art. Variouschanges and modifications are possible without departing from the spiritand scope of the invention described herein and will be apparent tothose skilled in the art to which it pertains. It is accordinglyintended that the present invention shall only be limited by the scopeof the claims.

What is claimed is:

1. A compound having the formula II ITIHCNIIR;

claim 1 in is 3. A compound according to which R methyl and R isisopropyl.

4. A compound according to claim 1 in which R is n-butyl and R is ethyl.

5. A compound according to n-butyl and R is isopropyl.

6. A compound according to ethyl and R is tert-butyl.

7. A compound according to n-propyl and R is tert-butyl.

8. A compound according to n-butyl and R is tert-butyl.

9. A compound according to tert-butyl and R is tert-butyl.

10. A compound according to claim 1 in which R methyl and R isl-methylbutyl.

11. A compound according to claim 1 in which R ethyl and R isl-methylbutyl.

12. A compound according to claim 1 in which R n-propyl and R isl-methylbutyl.

13. A compound according to claim 1 in which R; isopropyl and R isl-methylbutyl.

14. A compound according to claim 1 in which R methyl and R is1,1-dimethylbutyl.

15. A compound according to claim 1 in which R ethyl and R is1,1-dimethylbutyl.

claim 1 in which R claim which R claim 1 inwhich R claim 1 in which Rclaim 1 in which R 16. A compound according to claim 1 in which R;.,' isReferences Cited 11- 1'0 yl andR is 1,1-dimeth lbutyl.

E compfmnd according to claim 1 in which R3 is Blazek, Chem. Abstracts,vol. 45, col. 569-570 (1951). P WY and 5 is y y Ganapati, Chem.Abstracts, vol. 33, col. 2495 (1939).

fgi i igigiggg to clam 1 m 'Whlch R3 18 5 Thoms et al., Chem. Abstracts,vol. 14, pp. 3638-39 (1920). ga g g igfigg to clalm 1 m Whlch R3 is Doubct al., J. Am. Chem. Soc., vol. 80, pp. 2205-17 20. A compound accordingto claim 1 in which R is (1958) isopropyl and R is sec-butyl. 10 Hanschet al., Biochemica et Biophysica Acta, vol. 112

21. A compound according to claim 1 in which R is (1966), pp. 381-391.ethyl and R is neopentyl.

22' A compound according to claim 1 in which 3 is Johnston et al., J.Med. Chem., vol. 6, 669 679 (1963). n'butyl and R5 15 1SbutYL LEONZITVER, Primary Examiner 23. A compound according to claim 1 1n WhlCh Ris 15 n buty1 and R5 is neopentyL M. W. GLYNN, Assistant Examiner 24. Acompound according to claim 1 in which R is methyl and R is neopentyl.

25. A compound according to claim 1 in which R is 260552 R, 553 C,347.2, 347.7, 470, 471 A, 453 R; methyl and R is tert-butyl. 20 71120,88, 99, 111

